Pneumatic grain conveyer



July 7, 1925. 1,545,230

G. ,BERNERT PNEUMATIC GRAIN CONVEYER Filed Aug. 19, 1920 660576 fisrngrf ATTURNE') Patented July 7, 1925.

:. UNITED STATES.

GEORGE BERNERT, 0F MILWAUKEE, WISCONSIN. i

PNE MAT C GBAIJST CONVEYER.

a ncauba' filed 'Au ustfm, 1920. Serial No. 404,590.

To all whom it may concern: 7

Be it known that I, ,GEORGE BEnNER'r, =1 citizen of the United States, and resident of Milwaukee, in the county of Milwaukee and State of WVisconsin, have invented certain new and useful Improvements-in Pneumatic Grain Conveyers; and I do hereby declare that the following is a full. clear, and exact description thereof. 7

My invention relates to new and useful improvements in conveying apparatus for granular materials, and more particularly of the general type shown in my co-pending application for patent, filed February 9, 1920, Serial #357,450, and comprising an upwardly inclined pneumatic conveyer trunk port-ion having an opening in its top communicating with the upper end of the casing of a spiral feeding conveyer. V

The feeder casings of conveying apparatus of this type have heretofore been provided with hinged valves urged to closing position by spring or gravity action exerted adjacent the pivot of the valve, and inasmuch as it is desirable in the general construction to drive the shaft of the spiral conveyer from its upper end, said shaft is usually extended through a slot in the pivoted valve permitting a leakage of air through the feeding conveyer casing. This leakage fiow of air is desirable when itis wished to procure a cleaning action in the feed operation by the provision of a cleanervent as stated in my said co-pending'application, but in certain instances it is neither necessary nor desirable to efiect this cleaning action and in this event it becomes advantageous to prevent any retrograde flow of air in the conveyer trunk for the main conveying function.

It is therefore primarily the object of my invention to provide a valve structure-in the present type of conveying apparatus which will effect a complete closure of'the feeder casing against the admission of air, yet which is freely yieldable .to permit the proper passage of grain from the feeder cas-. ing into the conveyer trunk i It is further my object to accomplish this result by the provision of an arrangement whereby the valve is urged to its closing position by the gravity actionjincidental to its own Weight, and whereby the resistance of the valve to opening movement is consequently substantially uniform throughout the entire pathv of travel ofthe valve, in contra-distinction to any feeding arrange ment including a sliding valve member and wherein the closing action of the valvemem her would be procured by a spring bearing thereagainst, thespring action increasing in opening movement of the valv'eto such degree as to interfere with'the opening movement if the spring possesses initially sufliafter describedand pointed out in the appended claims. 1

In the accompanying drawings; F1gure-1 1s a slde elevat onof a pneumatic gram conveying apparatus embodying my invention. and having portions of thefeeder v ca'singand air trunk broken away to more clearly disclose the invention.

Figurel2 is a detailed-sectional view on the line 22 of Figure l. i

Referring now more particularly tothe accompanying drawings, 5 designates the usual blower fan casing which. is mounted on a suitable base 6 and hasa pneumatic conveying trunk 7 extending obliquely upward: ly therefrom, the lower portion of said trunk being provided with the usual collector pocket '8 for surplus grain tending to drop down into the fan casing, and while I have shown conventionally a belt drive extending to the collector pocket for actuating mechanical means for clearing graintherefrom, it will be appreciated that the accumulated grain may be cleared from the collector pocket in any dcsiredmanner. v j

This conveyer trunk is, in the present in-' stance, square in cross-section and is provided in its top, at a point above the c01 lector pocket 8, with an inlet opening 9 over which is disposed a square boxing 10 which forms the 'upper end portion of the feeder casing, the major portion of said casing bein formed by a cylindrical section 11 which is inclined upwardly'from a feeding hopper 12. A spiral conveyerblade 13 is extended through the cylindrical casing portion "ll terminating just short ofthe box 10, and the shaft 14 of the conveyer blade is extended through the box 10 for drive gear connection 15 with a countershaft 16 which is suitably supplied with power. The cylindrical casing portion 11 enters the lower wall of the box portion 10 of the casing and a shoulder is consequently formed within the casing which forms a valve seat. A disk valve 17, slightly larger in diameter than the diameter of the cylinder 11, is providedfor engagement on this seat, said valve being carried by a collar 18 slidable on theupper end portion of the conveyer shaft 14.

It is particularly noted that the inclination of the feeder conveyer casing and consequently of the shaft 14 is such that the valve 17 will move downwardly to closing position by the gravity actionof its own weight, and this weight may, if necessary, be increased by the securement of a weight block 19 to the upper face of thevalve. I

may, in certain instances, employ a very light spring 20, coiled on the shaft it above the valve for the purpose of starting the gravity impelled closing movement of the valve, in: the event that a slight sticking of the valve would be encountered, it being appreciated that a very slight impetus may be effective to start positive'inovement of a member by gravity. This spring, however,

would be eliminated in the majority of cases and is. not to be considered a medium for closing the valve, for if the spring were made of sufficient strength to exert any positive closing action adjacent the closing position of the valve, .said spring would possess such tension upon opening movement of the valve as to materially retard such opening movement and impose excessive power requirements upon the feed conveyer action. 'For this reason, a spring pressed valve, such as shown in. gPatent #1,002,556, granted to myself and Jacob Bernert, Sept. 5,1911, is not operative since a spring is'r'elied upon to close the valve and closing pressure of the spring would cause binding action of the valve in addition to the excessive tension."

In the operation of the present structure, the valve 17 is held positively closed by gravity and the back pressure of air and effects a complete seal of the feed conveyer casing, and as grain is fed upwardly in the casing it will move the valve upwardly a distance contingent upon the rate and volume of grain interposed between the valve and its seat serving to prevent retrograde flow of air, and as the feeding ofthe grain is reduced, the valve will promptly move. to its closing position, this opening and closing movement of the valve beinmthus readily secured and imposing no unc ue load upon the feeding mechanism. 1

To reduce the retarding action of back pressure on the feeding action, I provide a deflector lip 21 inclined inwardly a short distance from the lower edge of the feed opening '9 of the air trunk, whereby the current of air flowing through the trunk is slightly deflected immediately adjacent the valve and hence produces a reduced pressure area in the open upper end portion of the feeder casing constituted by the box 10, thus preventing the exertion of back pressure on the valve and on the'grain as it is fed past the valve. This deflector lip 21 reduces the cross-sectional area of the trunk at the point at which saidlip is located and column since the blower fan merely exerts a certain degree of head pressure over a certain area and will not be operable to further compress the air. To thus maintain the proper air velocity, the air trunk is reduced in cross-section a very short distance beyond the feed opening 9, and is continued to the distance of conveying action with this reduced cross-section. This reduced cross-section is substantially equal to-the reduction of cross-section caused by the disposition of the deflector lip 21, and thus at the points marked a in the drawing the cross-sections are substantially equal, The fan may be thus designed for the proper air velocity at the cross-sectional areas a, and the excess space in the lower portion of the duct merely banks up idle air. I am aware that deflector lips have been heretofore employed in feeding materialinto a pneumatic duct,

but the provisionof such deflector lips has heretofore served to reduce the general cross-' sectional area of the trunk, resulting either in the decrease of the. conveying velocity "or in the necessity of providing an excessive fan action to procure the required velocity,-

and no one has heretofore contemplated the reduction of the major portion of the trunk to correspond to the reduced cross-sectional area resulting from the provision of a de flector lip in the trunk.

1 To prevent grain from possibly jumping past the collector'pocket 8 under adverse conditions of conveying, I provide a wall 22 which extends inwardly from the juncture of the lower side of the pocket with the duct and then is directed longitudinally in the direction of the duct over the area of the pocket, the forward edge of the wall being spaced from the edge of the lip a distance equal to the width of each of the cross-sectional areas a whereby to avoid choking the cross-sectional areaand the major portionpositivetrap; for grain travelling down--.

lower portion'of the duct'to-thus provide a ing communicating with said box, -the: por= wardly at the lower "portion of the duct. I have further discovered that back pressure ofair exerted in the feeder casing has.

an exaggerated retarding action in connecsaid back pressure of air increases the dens'ity of the grain carried in the convolutions of the spiral conveyer andhence increases the friction action of the grain against'the' casing along the line ofthe spiral conveyer, in addition to the direct retrograde thrust of said back pressure on ithe'columnof 'grain and thus the provision'of the deflector lip 21 and theavoidance of valve spring tension possesses particular advantages in connection withthe positive feed means 'afl'or'ded by the spiral conveyer. r

While I have shown and described a preferred embodiment of my invention,-'it' will be appreciated that various changes and modifications of structure and arrangement may be employed without departing in any manner from the spirit of the invention. For instance, while the collector pocket wall 22 in the air duct extends over the body of the pocket and thus provides a means for shielding the pocket from direct pressure of the grain conveying current of air, it is seen that a further essential grain trapping relation is provided by the fact that the side wall of the pocket adjacent the fan extends closer to the top of the air duct than does the other side wall of the pocket to thus afford a deflecting abutment for grain sliding downwardly through the duct.

WVhat is claimed is:

1. A pneumatic conveyer apparatus including an air duct, an upwardly extended feeder conveyer casing communicating at its upper end portion with said duct, a valve seat in the upper end portion of the feeder conveyer casing, a valve slidably mounted in the upper end portion of said casing and movable to engage by gravity against said seat, and means for conveying material upwardly in said casing to open said valve and feed said material therepast into the duct.

2. A pneumatic conveyer apparatus including an air duct, anupwardly extended feeder conveyer casing communicating at its upper end portion with said duct, a spiral conveyer in the casing, a shaft for said spiral conveyer extended in the top portion of the casing, and a valve disk slidably mounted on said shaft and movable thereon to closing position against the seat by the gravity action of the weight of said valve incidental to the inclination of the said shaft.

3. A pneumatic conveyer apparatus including an air duct provided with an opening in its top, a box disposed in said opening, an upwardly extended cylindrical castion ofsaid box adjacent said casing forming a Valve seat a spiral conveyerin-said easing, a shaft forsaidspiralconveyerex tended in the box, and a 'valvediskslidably 1 mounted j on said "shaft and movable thereon I to closing position againstgthe'seat byfthe gravity action of the weight of :said valve incidental to the inclination of the :said shaft. --;j'z

4. A pneumatic conveyer apparatus including "an-air duct provided with Ia: feed: opening in its top, a blower fan communicating with said duct for procuring a pres-I sure current of-'airtherein, a feeder conveyer casing communicating with said I feed opening of the duct, a'conveyer in said casing for forcing "grain "therethrough, and Ya deflector lip in the duct at the side of its feed opening-adjacent theblower fanfor deflecting back pressure current of air from the said 'conveyer,'the cross-sectional. area of the major portion of said duct'norresponding to the reduced cross-sectional area resulting from the provision of said deflectorlip. I

5. A pneumatic conveyer apparatus including an air duct provided with a feed opening in its top, a blower fan communicating with said duct for procuring a pressure current of air therein, a feeder conveyer 4 sectional area of the duct at any point between the lip'and the fan, and the crosssectional area of the duct being reduced beyond and adjacent the feed opening to correspond to' the reduction of cross-section by said lip whereby to maintain the effective pressure current conditions determined by the cross-sectional area of the duct at the lip.

6. cluding an air duct provided with a feed opening in its top, a blower fan communicating with said duct for procuring a pressure current of air therein, a feeder conveyer casing communicating with said feed opening of the duct, a conveyer in said casing for forcing grain therethrough, a deflector lip in the duct at the side of its feed opening adjacent the blower fan for deflecting back pressure current of air from the said conveyer, the cross-sectional area of said duct at said lip being less than the crosssectional area of the duct at any point be- A pneumatic conveyer apparatus intween the lip and the fan, and the crossrespond to the reduction. of cross-section by said lip whereby to maintain the efi'ective pressure current conditions determined by the cross-sectional areaof the duct at the lip, and a. collector pocket disposed below the feed opening of the duct,'the mouth of said pocket extending transversely of the lower portion of the duct and occupying the transverse space. defined by the increased area of the said portion of the duct. 7. A pneumatic conveyor apparatus including an air duct provided with a feed opening in its top, a blower fan communicat ing with the lower end of said duct for procuring a pressure current of air there-in, means for feeding grainthrough said feed opening, and a collector pocket communi-v cating with the lower portion of theyduc below the. feed: opening, the wall of the collector pocket; adjacent the fan extending closer to the top of the duct than the other wall of the pocket, whereby to define a grain deflecting abutment within the-duct.

portion of the duct below the feed opening, v 1

the wall of the collector pocket adjacent'the fan extending closed to thetopof the duct than; the other wall of the pocket whereby to define agrain deflecting abutment within the duct, and a deflector lip in the duct at the side of its feed opening adjacent the blower fan. I

In testimony that I claim the foregoing I have hereunto set my hand at Milwaukee, in the county of Milwaukee and State of Wisconsin.

enonen BERNERT, 

